Limitations of a ZN-PI Controller for Liquid Level Control of Horizontal Cylindrical Tank
Keywords:
Horizontal Cylindrical Tank, ZN-PI Controller, Liquid Level Control, Nonlinear ProcessAbstract
Most chemical processes are inherently nonlinear. However, because of their simplicity, linear control algorithms have been used for the control of nonlinear processes. In this work, horizontally placed cylindrical tanks whose parameters vary with respect to process variable are considered for study. [ Anandanatarajan, R.,Chidambaram,M., and Jayasingh, T., Limitations of PI controller for a first- order nonlinear process with dead time. ISA transactions 45, 185-199(2006)]. The time constant and gain of the chosen process vary as a function of level. The limitations of the conventional PI controller tuned using Ziegler Nichols (ZN) settings for the chosen process are carried out. The servo and regulatory responses for various magnitudes of set point changes and load changes at various operating points with the controller tuned only at a chosen nominal operating point are obtained. Simulation is conducted within MATLAB environment to verify the performances of the system in terms of Settling Time, Overshoot (OS) and Simulation is conducted within MATLAB environment to verify the performances of the system in terms of Settling Time and Overshoot (OS)
References
- Zeigler, J. and Nichols, N. “Optimum Settings for Automatic Controllers”, Transactions of ASME, Vol. 64, pp. 759–768, 1942.
- Cohen, G.H. & Coon, G.A., 1953. Theoretical Consideration of Retargeted Control. Transaction ASME, 75, pp.827-34.
- Astrom, K. J., & Hagglund, T. (1984). Automatic tuning of simple regulators with specifications on phase and amplitude margins. Automatica, 20(5), 645–651.
- Anandanatarajan, R.,Chidambaram,M., and Jayasingh, T., Limitations of PI controller for a first- order nonlinear process with dead time. ISA transactions 45, 185-199(2006).
- Tore Hagglund (1992), 'A predictive PI Controller for Processes with long dead times', IEEE Control Systems Magazine, Vol. 12(1) pp. 57-60.
- Su Whan Sung and In-Beum Lee (1996), 'Limitations and countermeasures of PID controllers', Ind. Eng. Chem. Res., Vol. 35, pp. 2596-2610.
- Babatunde A. Ogunnalke., Controller design for nonlinear process system via variable transformations Ind.eng. chem. process. Des. Dev. 25, 241-248(1986)
- Tian, Y.C. and Gao, F., Double-controller scheme for control of processes with dominant delay. IEEE Proc. Control Theory Appl. 145(5), 479-484(1998).
- J.M. Smith, Closed control of loops with dead time, Chemical Engineering Progress 53, may,217-219(1953).
- Satean Tunyasrirut, and Santi Wangnipparnt “Level Control in Horizontal Tank by Fuzzy-PID Cascade Controller” - World Academy of Science, Engineering and Technology 25 -2007.
- J.C Basilio and S.R.Matos, 'Design of PI and PID Controllers With Transient formance Specification' . IEEE transaction on education,vol.45 , no.4. November 2002, pages 364-370
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